1. Field of the Invention
The invention relates to a device for automatic locking/unlocking by gravity for locking the lid of a container on the top edge of the vessel of the container. This container is intended to be emptied by tilting. It can notably be used for the collection of waste.
2. Description of Related Art
Containers intended for waste collection need to stay on the public highway whilst awaiting the passage of the vehicles intended to collect the waste.
These containers, left without supervision, may be searched through, which may prove dangerous depending on the nature of the waste contained in the containers.
In the context of the selective collection of waste, the lids on the containers are provided with an opening with a size and shape adapted to the waste which is to be disposed in these containers.
The absence of a locking device for these containers may allow their unwanted filling with inappropriate waste making such a so-called xe2x80x9cselectivexe2x80x9d collection ineffective.
A system for locking the container whilst it is being filled and for unlocking it when it is emptied therefore proves necessary.
A certain number of patents refer to locking/unlocking systems for waste container lids.
By way of example, the documents EP-A-698 567 and EP-A-704 387 refer to a locking system which engages, after the closure of the lid, in a support element, so that the lid is protected against opening.
In the case of the document EP-A-698 567, the opening of the lid takes place by the electromagnetic actuation of a device which acts on the support element in which the locking system engages.
In the case of the document EP-A-704 387, the opening of the lid takes place by means of an operating button.
In these two cases, the opening of the lid requires a manoeuvre, notably manual, on the part of the operator and may take place whatever the position of the container in space.
The documents FR-A-2 762 306 and EP-A-872 432 describe a device for locking the lid of a container on the vessel of the said container not requiring the manual intervention of the operator to allow the locking or unlocking of the lid.
The locking device described in these documents has a pivoting piece pivotally mounted under the container lid and coming into engagement with a male attachment device situated on the internal wall of the container.
When a container provided with such a locking device is in the filling position, the pivoting piece adopts a locked position in which it is in engagement with a male attachment device causing the lid to be maintained in the closed position.
When the same container is tilted by a skip lorry, for example, in order to be emptied into the skip thereof, the pivoting piece passes from its locked position to an unlocked position in which it is released from the attachment device under the effect of gravity.
The tilting of the container thus allows the opening of the lid on the container and therefore the emptying of the latter by discharging the waste under the effect of gravity.
Given the size and weight of such waste containers, the tilting operation is practically exclusively reserved for skip lorries intended for this purpose and in practice cannot be carried out by a third party. This has the effect of preventing the opening of the containers by a third party and thus preventing the filling of the containers with waste other than that for which they are intended.
All the types of locking/unlocking devices dealt with above have the major drawback of making it impossible to nest the containers since the lid locking mechanism occupies a not insignificant amount of space on the internal wall of the vessel.
This impossibility of nesting the containers when they are transported gives rise to an appreciable increase in transportation costs.
Moreover, the presence of a locking/unlocking device or of a housing on the internal wall of the container vessel, as described in the above mentioned documents, interferes with the flow of the waste when the container is emptied. This has the consequence of encouraging the accumulation of waste at the locking/unlocking device or housing and therefore complicates the maintenance and cleaning of the vessels.
The invention aims to afford solutions to these technical problems. It consists of a device for the locking/unlocking of a container without the manual intervention of the operator, the walls of the vessel being smooth and uniform, which allows the nesting of the containers and a good flow of the waste.
To this end, the invention proposes a locking/unlocking device for a waste collection container, the said container having a vessel and a lid associated with the vessel and being able to be moved between a closed position and an open position, the device enabling the container lid to be locked on the end part of the vessel when the container is in the filling position, and to be unlocked when the vessel is in the emptying position.
The device comprises a pivoting piece, itself comprising:
a lever fixed so as to be articulated on the internal face of the lid and projecting inside the container when the lid is in the closed position;
an arm extending the articulation of the lever extending underneath the internal face of the lid when the latter is in the closed position;
an intermediate part to which the lever and arm are fixed through which the axis of rotation of the said pivoting piece passes.
According to the invention, the lever has a retractable hook intended to be engaged in an orifice or hollow situated at the end part of the vessel, the arm having an end part, opposite to the intermediate part of the pivoting piece, coming into engagement with a hook forming part of an angled piece. The said angled piece comprises on the one hand a locking leg including the hook and on the other hand a driving leg and is articulated on an axis of rotation parallel to the axis of rotation of the pivoting piece, the driving leg of the angled piece being locked in the lid locking position by a stop. In addition, means are provided so that the tilting of the container at a certain angle causes, by gravity effect, the pivoting of the angled piece and, by gravity effect, the pivoting of the arm and of the lever towards an unlocked position.
According to the invention, when the container is in the filling position, the centre of gravity of the angled piece is situated so that it holds the driving leg of the angled piece in abutment on the stop and the hook on the angled piece in engagement with the end part of the arm on the pivoting piece, the centre of gravity of the assembly comprising the pivoting piece and the hook being situated so as to hold the retractable hook on the lever in the position of engagement in the orifice in the end part of the vessel and the end part of the arm in engagement with the hook on the angled piece. The tilting of the container through a certain angle with respect to the vertical when it is emptied gives rise to a movement of the said centres of gravity, causing a pivoting of the angled piece, releasing the hook on the angled piece from the end part of the arm on the pivoting piece, giving rise to the pivoting of the arm and of the lever, and, finally, leading to the disengagement of the retractable hook from the orifice in the vessel and therefore to the opening of the container lid.
According to other characteristics, the retractable hook on the lever is articulated on an axis substantially parallel to the axis of rotation of the pivoting piece, which allows, when the lid is closed on the end part of the vessel, a sliding of the retractable hook along the internal wall of the container until the retractable hook is inserted in the orifice or hollow situated at the end part of the vessel.
The pivoting of the arm about the axis of rotation of the pivoting piece, and the pivoting of the angled piece about its axis of rotation, in the opposite direction to the internal face of the container lid, are each limited by a stop.
The end part of the arm opposite to the intermediate part of the pivoting piece, and/or the free end part of the driving leg, has or have a weight.
According to a first embodiment, the angled piece has the shape of a V, the two legs of which form an angle of around 35 to 55 degrees, notably around 45 degrees.
According to a second embodiment, the angled piece has the shape of a V whose two legs form an angle of between 90 and 180 degrees.
According to a third embodiment, the locking/unlocking device comprises a rocker arm able to move in rotation about a shaft connected to the container lid and substantially parallel to the axis of rotation of the angled piece, the rocker arm being able to move between a locked position in which the rocker arm forms a stop opposing the pivoting of the angled piece towards the internal face of the lid, and an unlocked position in which the rocker arm does not oppose the said pivoting of the angled piece, the rotation of the rocker arm between the said locked and unlocked positions being obtained when the container is tilted at a certain angle, by gravity effect.
In a variant of the third embodiment, the rocker arm has the shape of a circular sector, the axis of rotation of the rocker arm being situated close to the apex of the said circular sector, and the free end edge of the rocker arm being, when the rocker arm is in the locked position, in contact with the driving leg of the angled piece.
The two legs of the angled piece may be able to move in rotation with respect to each other, about the axis of rotation of the angled piece, the driving leg of the angled piece comprising, towards its end part, a weight, so that, when the container is tilted at a certain angle, the locking leg on the angled piece being still in engagement with the arm, the driving leg of the angled piece can pivot about its axis, by gravity effect, and then strike the hook so as to release it from the arm.
In a variant, the driving leg of the angled piece comprises, towards its end part, a projection intended, when the container is titled at a cession angle, to strike the hook so as to release it from the arm.
The locking/unlocking device according to the invention can also include a release system fixed to the container lid and intended to be actuated by a control member, in order to unlock the lid from the container when the container is in the filling position.
The locking/unlocking device is protected by a housing fixed on the internal face of the lid and having an opening from which the retractable hook on the lever projects, the housing being able to form a stop for the angled piece, thus limiting its movement in the opposite direction to the internal face of the lid.
The locking/unlocking device also preferably has a device for protecting the retractable hook fixed to the container vessel.
According to a second aspect, the object of the invention is a container for collecting waste, having a locking/unlocking device as described above.